The assemblies, such as high-power IGBT, reactor, and other heat-generating assembly in a heat-dissipating system for cabinet, dissipate large amount of heat during operation. It is likely to cause assemblies damaged due to high temperature if large amount of heat can not be dissipated timely. Thereby, the arrangement of the heat-dissipating assemblies and the rational design of the air duct become very important.
As shown in FIG. 1, the conventional heat-dissipating system for high-power cabinet comprises: a cabinet 1-6, a first air duct 1-9 formed in the cabinet 1-6, a first fan 1-8 and a first heat-generating assembly 1-10 mounted in the first air duct 1-9. The first air duct 1-9 has a first air inlet 1-11 located on the side surface of the cabinet 1-6 and a first air outlet 1-7 located on the top surface of the cabinet 1-6. The first fan 1-8 is positioned on the top portion of the cabinet 1-6, with the air outlet of the first fan 1-8 facing away from the first heat-generating assembly 1-10.
Thus, during the process that the first fan 1-8 cools the first heat-generating assembly 1-10, the air flows through the first heat-generating assembly 1-10 firstly, and then flows through the first fan 1-8, i.e., the first fan 1-8 cools the first heat-generating assembly 1-10 in manner of sucking air. Airflow temperature rises after the air flows through the first heat-generating assembly 1-10, and the airflow with higher temperature flows through the first fan 1-8, which will have a negative effect on the service life of the first fan 1-8. Moreover, the conventional heat-dissipating system is highly noisy, because the first fan 1-8 is installed on the top portion of cabinet 1-6.
In the case that the heat-dissipating system further comprises other minor heat-generating assemblies, it is necessary to provide extra air ducts for minor heat-generating assemblies for heat dissipation, since these minor heat-generating assemblies generally do not share the same air duct with the first heat-generating assembly 1-10. Thereby, a second air duct 1-4 is mounted in the cabinet 1-6. The second air duct 1-4 has a second air inlet 1-12 located on the lower side surface of the cabinet 1-6 and a second air outlet 1-1 located on the top of the cabinet 1-6. Other minor heat-generating assemblies, such as a second heat-generating assembly 1-5, a third heat-generating assembly 1-3, are mounted in the second air duct 1-4. A second fan 1-2 mounted in the second air duct 1-4 is used for cooling the second heat-generating assembly 1-5 and the third heat-generating assembly 1-3.
As shown in FIG. 1, the second heat-generating assembly 1-5 and the third heat-generating assembly 1-3 are positioned under the second fan 1-2, and face away from the outlet of the second fan 1-2. Similarly, the service life of the second fan 1-2 will be affected negatively, due to the higher temperature airflow sucked into the second fan 1-2. Additionally, the conventional heat-dissipating system is highly noisy, because the second fan 1-2 is installed on the top portion of cabinet 1-6.